JP7635472B1 - Sealed structure - Google Patents

Abstract

To provide a sealing structure capable of suppressing a part of a gasket from floating up from a mounting groove when the gasket is mounted in the mounting groove.
The gasket 300 comprises an annular gasket main body 310 that is mounted in the mounting groove 210, and a plurality of protrusions 320 that are provided at intervals in the circumferential direction on the inner surface of the gasket main body 310, and is characterized in that when the gasket 300 is mounted in the mounting groove 210 and before the first member and the second member are fixed, the protrusions 320 contact one side wall surface of the mounting groove 210, and the gasket main body 310 has a serpentine portion 312 that does not contact the side wall surfaces on both sides of the mounting groove 210.

Description

The present invention relates to a sealing structure.

In engine and transmission cases, a sealing structure with a gasket is provided to prevent oil and the like from leaking out of the case. With reference to Figure 7, the sealing structure of a case according to the conventional technology will be explained. Figure 7(a) is a plan view of a gasket according to the conventional technology, and Figure 7(b) is a bottom view showing the state in which the gasket is attached to the members that make up the case.

Generally, a case is composed of a case body with an opening and a lid member for closing the opening of the case body. When a sealed structure is provided, a gasket is provided to seal the gap between the end faces of the case body and the lid member.

In the example shown in Figure 7, a gasket 500 is fitted into an annular fitting groove 210 provided in the lid member 200, and the lid member 200 is fixed to a case body (not shown), thereby forming a sealed structure. That is, when the case body and the lid member 200 are fixed, the gasket 500 fitted into the fitting groove 210 is compressed by the case body and the lid member 200, and the gap between the end faces of the case body and the lid member 200 is sealed.

The gasket 500 may be transported while attached to the lid member 200, and the lid member 200 may be fixed to the case body after various components and devices are assembled in the case body. In such a case, it is necessary to prevent the gasket 500 from falling off from the mounting groove 210 during transportation. Therefore, the gasket 500 has a plurality of projections 520 for preventing falling off spaced apart in the circumferential direction on the inner peripheral surface of the annular gasket body 510 that is attached to the mounting groove 210. When the gasket 500 configured as described above is attached to the mounting groove 210, the outer peripheral surface of the gasket 500 contacts the outer peripheral side wall surface of the mounting groove 210, and the plurality of projections 520 contact the inner peripheral side wall surface of the mounting groove 210. As a result, the gasket 500 is compressed in the width direction, and falling off from the mounting groove 210 is suppressed.

In the gasket 500 configured as described above, when the gasket 500 is fitted into the fitting groove 210, a part of the gasket 500 may lift up from the groove, reducing workability. In particular, when the fitting groove 210 is shallow due to various constraints, it has been found that the linear portion between adjacent protrusions 520 of the gasket body 510 is likely to lift up. The following points are considered to be the cause of this. That is, when the gasket 500 is fitted into the fitting groove 210, the gasket 500 is compressed in the width direction at the protrusion 520 portion. As a result, a force acts to compress the linear portion between adjacent protrusions 520 of the gasket body 510 in the linear direction. Therefore, a force acts on the linear portion to deform it so that it lifts up from the fitting groove 210, and when this force exceeds the frictional force between the linear portion and the side wall surface of the fitting groove 210, the portion lifts up. In particular, it is believed that the shallower the groove depth of the mounting groove 210, the smaller the contact area between the linear portion and the side wall surface of the mounting groove 210 and the smaller the frictional force, making it easier for the mounting groove 210 to lift up.

International Publication No. WO 2007/7611

The present invention provides a sealing structure that can prevent a portion of a gasket from floating up from an installation groove when the gasket is installed in the installation groove.

The present invention adopts the following means to solve the above problems.

That is, the sealing structure of the present invention is as follows:
A first member;
A second member fixed to the first member;
a gasket that is attached to an annular attachment groove provided in at least one of the first member and the second member and seals a gap between end faces of the first member and the second member;
A sealing structure comprising:
The gasket is
an annular gasket body portion that is fitted into the fitting groove;
A plurality of protrusions are provided at intervals in the circumferential direction on an inner circumferential surface or an outer circumferential surface of the gasket body;
With
When the gasket is mounted in the mounting groove and before the first and second members are fixed, the protrusion contacts one side wall surface of the mounting groove, and the gasket main body has a serpentine portion that does not contact both side wall surfaces of the mounting groove.

According to the present invention, the gasket body has a serpentine portion that does not contact the sidewalls on either side of the mounting groove. As a result, even if a compressive force acts on the portion of the gasket body between adjacent protrusions by mounting the gasket in the mounting groove, the force is absorbed by the serpentine portion, and the force that causes the gasket to deform and rise up from the mounting groove is suppressed.

When the gasket is mounted in the mounting groove and before the first and second members are fixed, the gasket body except for the serpentine portion may contact one of the side wall surfaces on both sides of the mounting groove that is opposite to the side wall surface with which the protrusion contacts.

This more reliably prevents the gasket from falling out of the mounting groove.

The protrusion may have a cavity.

This reduces the repulsive force when the protrusion is compressed, further preventing the gasket from floating up.

As described above, the present invention makes it possible to prevent a portion of the gasket from floating up from the mounting groove when the gasket is mounted in the mounting groove.

FIG. 1 is an explanatory diagram of a case having a sealing structure according to a first embodiment of the present invention. FIG. 2 is a schematic diagram of a gasket according to the first embodiment of the present invention. FIG. 3 is an explanatory diagram of a sealing structure according to the first embodiment of the present invention. FIG. 4 is an explanatory diagram of a sealing structure according to a second embodiment of the present invention. FIG. 5 shows a modified example of the gasket. FIG. 6 shows a modified example of the gasket. FIG. 7 is an explanatory diagram of a sealing structure according to the prior art.

The following describes in detail the embodiments of the present invention with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, and relative positions of the components described in the embodiments are not intended to limit the scope of the present invention to those.

Example 1
A sealing structure according to a first embodiment of the present invention will be described with reference to Figs. 1 to 3. Fig. 1 is an explanatory diagram of a case having a sealing structure according to a first embodiment of the present invention, in which Fig. 1(a) is an external view of the case, Fig. 1(b) is a plan view of the case body, and Fig. 1(c) is a bottom view of the lid member. In Fig. 1(a), a partly see-through portion is indicated by a dotted line. Fig. 2 is a schematic diagram of a gasket according to a first embodiment of the present invention, in which Fig. 2(a) is a plan view of the gasket, Fig. 2(b) is a cross-sectional view taken along A1-A1 in Fig. 2(a), and Fig. 2(c) is a cross-sectional view taken along B1-B1 in Fig. 2(a). Fig. 3 is an explanatory diagram of a sealing structure according to a first embodiment of the present invention, in which Fig. 3(a) is a bottom view showing a state in which the gasket is attached to the lid member, Fig. 3(b) is a cross-sectional view taken along A2-A2 in Fig. 2(a), and Fig. 3(c) is a cross-sectional view taken along B2-B2 in Fig. 2(a).

<Sealing structure>
An outline of the sealing structure will be described with reference to Fig. 1. The case 10 shown in Fig. 1 is composed of a case body 100 as a first member and a cover member 200 as a second member. The case 10 according to this embodiment is preferably used as a case for an engine or a transmission. However, the case described below is not limited to such an application and can be applied as a case for various applications. The sealing structure of the present invention is not limited to a sealing structure provided on a case and can be applied to various sealing structures that require sealing between end faces of two members.

An opening 110 is provided in the case body 100, and various components and devices are accommodated through the opening 110. The opening 110 is closed by fixing the cover member 200 to the case body 100. The fixing structure between the case body 100 and the cover member 200 may be a structure using fasteners such as bolts, or various known techniques may be used.

Then, a gasket 300 is provided to seal the gap between the end faces of the case body 100 and the lid member 200, and a sealed structure is formed by these members. The gasket 300 is made of an elastomer material such as rubber. In this embodiment, the gasket 300 is attached to the annular mounting groove 210 provided in the lid member 200, and the gap between the end faces of the case body 100 and the lid member 200 is sealed. That is, the gasket 300 is compressed by the end face 105 of the case body 100 and the groove bottom surface of the annular mounting groove 210 provided in the end face of the lid member 200, and the gap between the end faces of the case body 100 and the lid member 200 is sealed. The mounting groove for mounting the gasket may be provided in the case body, or a configuration in which it is provided in both the case body and the lid member can be adopted.

<Gasket>
The configuration of the gasket 300 will be described with particular reference to Fig. 2. The gasket 300 includes an annular gasket body 310 that is fitted into the fitting groove 210, and a plurality of protrusions 320 that are provided at intervals in the circumferential direction on the inner peripheral surface of the gasket body 310. The gasket body 310 is configured with a portion whose planar shape is similar to that of the fitting groove 210 (for convenience, hereinafter referred to as "similar shape portion 311") and a serpentine portion 312 so as to fit along the fitting groove 210. The serpentine portion 312 has a serpentine shape so as to protrude in the same direction as the protrusions 320 (in this embodiment, the direction from the outer peripheral surface toward the inner peripheral surface).

In this embodiment, a pair of annular seal protrusions 313, 314 are provided on one of the front and back surfaces of the gasket body 310, and a pair of annular seal protrusions 315, 316 are provided on the other surface. In this embodiment, the gasket 300 is symmetrical with respect to the center plane in the front and back directions of the gasket 300, so there is no need to pay attention to the direction when mounting the gasket 300 in the mounting groove 210. In addition, in the present invention, a configuration in which no seal protrusions are provided on the front and back surfaces of the gasket body, a configuration in which a single annular seal protrusion is provided on each of the front and back surfaces, and a configuration in which three or more annular seal protrusions are provided on each of the front and back surfaces may also be adopted. In addition, in the present invention, a configuration in which the gasket has an asymmetric shape with respect to the center plane in the front and back directions may also be adopted. In this case, a configuration in which the number of annular seal protrusions on both sides is different, such as a configuration in which a single annular seal protrusion is provided on one of the front and back surfaces of the gasket body and a pair of annular seal protrusions is provided on the other surface, may also be adopted. Of course, a configuration may also be adopted in which no annular seal projection is provided on one surface side, and a single or multiple annular seal projections are provided on the other surface side.

<Gasket installed in the installation groove>
With particular reference to FIG. 3, the relationship between the gasket 300 and the mounting groove 210 in a state in which the gasket 300 is mounted in the mounting groove 210 and before the case body 100 and the cover member 200 are fixed will be described. In this state, the multiple protrusions 320 are configured to contact one side wall surface of the mounting groove 210 (in this embodiment, the side wall surface on the inner periphery). This makes it possible to prevent the gasket 300 from falling off from the mounting groove 210. In other words, the multiple protrusions 320 play a role as protrusions for preventing falling off. In addition, in the above state, the portion of the gasket main body 310 other than the meandering portion 312 (i.e., the similar shape portion 311) is configured to contact the side wall surface on the opposite side to the side wall surface that the protrusions 320 contact, among the side wall surfaces on both sides of the mounting groove 210 (in this embodiment, the side wall surface on the outer periphery). This makes it possible to more reliably prevent the gasket 300 from falling off from the mounting groove 210.

In this embodiment, in the above state, the serpentine portion 312 is configured not to contact the side wall surfaces on both sides of the mounting groove 210 (see Figs. 3(a) and (c)). When the case body 100 and the lid member 200 are fixed, the gasket 300 is compressed and deformed by them. In this state, part or all of both sides of the serpentine portion 312 may be configured to contact the side wall surfaces on both sides of the mounting groove 210.

<Advantages of the sealing structure according to this embodiment>
According to the sealing structure of this embodiment, the gasket body 310 has a configuration having a serpentine portion 312 that does not contact the side wall surfaces on both sides of the mounting groove 210. As a result, even if a force compressing a portion between adjacent protrusions 320 of the gasket body 310 acts by mounting the gasket 300 in the mounting groove 210, the force is absorbed by the serpentine portion 312. In other words, since there is a gap between the serpentine portion 312 and the side wall surface of the mounting groove 210, even if the above-mentioned force acts, the serpentine portion 312 can deform so as to protrude further in the direction from the outer peripheral surface toward the inner peripheral surface. This allows the above-mentioned force to be released. Therefore, the force that deforms a part of the gasket body 310 so that it floats up from the mounting groove 210 is suppressed, and the floating up can be suppressed. As a result, the workability of mounting the gasket 300 to the mounting groove 210 can be improved.

Example 2
4 shows a second embodiment of the present invention. In the first embodiment, the protrusions are provided on the inner peripheral surface of the gasket body, but in this embodiment, the protrusions are provided on the outer peripheral surface of the gasket body. Since the other basic configurations and functions are the same as those in the first embodiment, the same components are denoted by the same reference numerals and their description is omitted.

4 is an explanatory diagram of a sealing structure according to a second embodiment of the present invention, in which FIG. 4(a) is a plan view of the gasket, and FIG. 4(b) is a bottom view showing the state in which the gasket is attached to the lid member. The gasket 300A according to this embodiment includes an annular gasket body 310A that is attached to the attachment groove 210, and a plurality of protrusions 320A that are provided at intervals in the circumferential direction on the outer peripheral surface of the gasket body 310A. The gasket body 310A is composed of a similarly shaped portion 311A whose planar shape is similar to that of the attachment groove 210 and a serpentine portion 312A so as to follow the attachment groove 210. The serpentine portion 312A has a serpentine shape so as to protrude in the same direction as the protrusion 320A (in this embodiment, the direction from the inner peripheral surface toward the outer peripheral surface).

In this embodiment, as in embodiment 1, annular sealing protrusions are provided on the front and back surfaces of the gasket body 310A. The annular sealing protrusions are the same as those described in embodiment 1, and therefore will not be described here.

The relationship between the gasket 300A and the mounting groove 210 in a state where the gasket 300A is mounted in the mounting groove 210 and before the case body 100 and the lid member 200 are fixed will be described. In this state, the multiple protrusions 320A are configured to contact one side wall surface of the mounting groove 210 (in this embodiment, the outer peripheral side wall surface). This makes it possible to prevent the gasket 300A from falling off from the mounting groove 210. In other words, the multiple protrusions 320A play a role as protrusions for preventing falling off. In addition, in the above state, the portion of the gasket main body 310A other than the meandering portion 312A (i.e., the similar shape portion 311A) is configured to contact the side wall surface on the opposite side to the side wall surface that the protrusions 320A contact (in this embodiment, the inner peripheral side wall surface) of the side wall surfaces on both sides of the mounting groove 210. This makes it possible to more reliably prevent the gasket 300A from falling off from the mounting groove 210.

In this embodiment, in the above state, the serpentine portion 312A is configured not to contact the sidewalls on both sides of the mounting groove 210 (see FIG. 4(b)). When the case body 100 and the lid member 200 are fixed, the gasket 300A is compressed and deformed by them. In this state, part or all of both sides of the serpentine portion 312A may be configured to contact the sidewalls on both sides of the mounting groove 210.

The sealing structure of this embodiment configured as described above can also achieve the same effects as in Example 1 above.

(Modification)
A modified example of the gasket will be described with reference to Figs. 5 and 6. In the gasket 300 of the first embodiment, the meandering portion 312 is configured to meander so as to protrude in the same direction as the protrusion 320 (direction from the outer peripheral surface to the inner peripheral surface). However, the meandering portion may be configured to meander so as to protrude in the opposite direction to the protrusion direction. Fig. 5(a) shows a gasket 300B configured to meander so that the meandering portion 312B protrudes in the opposite direction to the protrusion direction of the protrusion 320 (direction from the inner peripheral surface to the outer peripheral surface). Note that Fig. 5(a) is a plan view of the gasket 300B, and the same components as those of the first embodiment are given the same reference numerals. In this gasket 300B, as in the first embodiment, it is desirable that not only the protrusion 320 but also the opposite side (direct back) of the protrusion 320 contact the side wall surface of the mounting groove 210 before the case body and the lid member are fixed. This makes it possible to more reliably prevent the gasket 300B from falling off the mounting groove 210. In the above state, the meandering portion 312B is configured not to come into contact with the side wall surfaces on both sides of the mounting groove 210, as in the first embodiment. Fig. 5(b) shows the gasket 300B mounted in the mounting groove 210.

Similarly, the gasket 300A of the second embodiment may be configured to have a serpentine shape such that the serpentine portion protrudes in the opposite direction to the protrusion direction of the protrusion. That is, as shown in FIG. 5(c), the gasket 300C may be configured to have a serpentine shape such that the serpentine portion 312C protrudes in the opposite direction to the protrusion direction of the protrusion 320 (from the outer peripheral surface toward the inner peripheral surface). The state before the gasket 300C is attached to the attachment groove and the case body and the lid member are fixed is the same as in the above embodiment and modified example, so a description thereof will be omitted.

The number and arrangement of the protrusions are not particularly limited. For example, in Example 1, a configuration was shown in which a protrusion 320 is provided at one location on each of the similarly shaped portions 311 between adjacent meandering portions 312 in the longitudinal direction of the gasket 300. However, for example, as in the gasket 300D shown in FIG. 6(a), a configuration in which similarly shaped portions 311 with protrusions 320 and similarly shaped portions 311 without protrusions 320 are arranged at appropriate positions can also be adopted. Although not particularly shown, a configuration in which multiple protrusions 320 are provided on one similarly shaped portion 311 can also be adopted.

In addition, in each of the above embodiments, the meandering portion is configured to be curved only toward either the inner circumferential surface side or the outer circumferential surface side in the planar shape. However, for example, as shown in Figures 6(b) and (c), meandering portions 312X and 312Y that are curved toward the inner circumferential surface side and the outer circumferential surface side, respectively, can also be used. It goes without saying that the number of portions that are curved toward the inner circumferential surface side or the outer circumferential surface side is not limited.

It is also possible to adopt a configuration in which a cavity 321 is provided in the protrusion 320E, as in the case of gasket 300E shown in Figure 6(d). Note that Figure 6(d) is a view equivalent to the A1-A1 cross-sectional view in Figure 2(a), similar to Figure 2(b). In this way, by adopting a configuration in which a cavity 321 is provided in the protrusion 320E, the repulsive force when the protrusion 320E is compressed is suppressed. This makes it possible to further suppress the floating of the gasket 300E when the gasket 300E is attached to the attachment groove.

In addition, in each of the above embodiments and modified examples, a configuration in which the serpentine portion is provided in multiple locations is shown, but if the floating of the gasket can be suppressed due to factors such as the dimensions of the gasket and the mounting groove, the serpentine portion may be provided in at least one location.

10: Case 100: Case body 105: End face 110: Opening 200: Lid member 210: Mounting groove 300, 300A, 300B, 300C, 300D, 300E: Gasket 310, 310A: Gasket body 311, 311A: Similar shaped portion 312, 312A, 312B, 312C, 312X, 312Y: Serpentine portion 313, 314, 315, 316: Seal protrusion 320, 320A, 320E: Protrusion 321: Cavity

Claims (3)

A first member;
A second member fixed to the first member;
a gasket that is attached to an annular attachment groove provided in at least one of the first member and the second member and seals a gap between end faces of the first member and the second member;
A sealing structure comprising:
The gasket is
an annular gasket body portion that is fitted into the fitting groove;
A plurality of protrusions are provided at intervals in the circumferential direction on an inner circumferential surface or an outer circumferential surface of the gasket body;
With
A sealing structure characterized in that, when the gasket is installed in the installation groove and before the first and second members are fixed, the protrusion contacts one side wall surface of the installation groove, and the gasket main body has a serpentine portion that does not contact both side wall surfaces of the installation groove. The sealing structure described in claim 1, characterized in that when the gasket is installed in the installation groove and before the first and second members are fixed, the portion of the gasket body excluding the serpentine portion contacts the side wall surface on both sides of the installation groove that is opposite to the side wall surface with which the protrusion contacts. A sealing structure as described in claim 1 or 2, characterized in that the protrusion is provided with a cavity.

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